The supply of safe, clean drinking water to all customers is a top priority at

Transcription

1 The supply of safe, clean drinking water to all customers is a top priority at anglianwater.co.uk Drinking water quality in 2008

2 Contents 02 Foreword 03 Drinking water quality in 2008 Drinking water compliance at water treatment works Drinking water compliance at storage points Drinking water compliance in our distribution system 04 Working with our customers 05 Safeguarding our customers drinking water Pitsford water treatment works Hydrocarbon contamination of customer pipework 06 Drinking water quality improvement programmes 06 Drinking Water Safety Planning and our Final Business Plan for Drinking water quality results Water treatment works Storage points Supply points Public water supply zones Find out more and contact us 1 Anglian Water Services Limited Drinking Water Quality Report 2008

3 Foreword I am pleased to present our Drinking Water Quality Report for We ve achieved excellent results, making continuous improvements in our supply of clean, safe drinking water. Clive Harward Head of Water Quality and Environmental Performance 99.98% Our 2008 mean zonal compliance figure of per cent was our highest since the Drinking Water Inspectorate (DWI) introduced the measure in Our compliance with the stringent standards for drinking water was excellent in 2008, and our mean zonal compliance figure of per cent was our highest since the Drinking Water Inspectorate (DWI) introduced the measure in We recorded more than a 30 per cent reduction in the number of exceedances of regulatory standards from 2007 to 2008, largely as a result of significantly fewer microbiological failures at customers taps. In June 2008 we faced a major challenge when we detected Cryptosporidia in routine water quality samples taken from the Pitsford water treatment works in Northamptonshire. We took the precautionary approach of advising customers in around 108,000 homes to boil their tap water. After rigorous independent investigations a number of recommendations were made, all of which we have acted upon. We have continued to make excellent progress in the delivery of our Drinking Water Quality programme in this current investment period (AMP4), and have completed the majority of new schemes well ahead of schedule. As we enter the final year of this investment period, we anticipate delivery of the remainder of our programme ahead of regulatory deadlines. Risk assessment and risk management are essential tools in the production of safe, clean drinking water, and we have continued to implement our Drinking Water Safety Planning approach throughout 2008, in line with new UK government requirements. We sent our Final Business Plan for to Ofwat in April this year, following the submission of our Strategic Direction Statement in December The Final Business Plan includes details of the investment required to ensure that we can continue to meet regulatory standards and protect public health. We will also develop our existing strong relationships with partner organisations on a number of emerging issues, particularly addressing deterioration in raw water quality and the introduction of a more stringent lead standard in Responding to our customers needs is very important to us, and we have improved the search by postcode facility on our website to help customers to find out about drinking water quality in their local area. Looking forward to the year ahead, we continue our focus on the good health of our customers, working in partnership with the DWI and the Royal College of Obstetricians and Gynaecologists to provide information on hydration and drinking water quality to expectant mothers. I hope you enjoy reading this report, which demonstrates our continual commitment to our primary goal to provide safe, clean drinking water to our customers. Clive Harward Head of Water Quality and Environmental Performance June Anglian Water Services Limited Drinking Water Quality Report 2008

4 Drinking water quality in % Mean zonal compliance in 2008 is per cent. Mean zonal compliance is the key measure used by the Drinking Water Inspectorate (DWI) to determine our overall compliance with the stringent regulatory drinking water standards in place in England and Wales. Mean Zonal Compliance Mean Zonal Compliance (%) In 2008, our mean zonal compliance was per cent. This is an increase from our 2007 figure (99.96 per cent) and is our highest value since the DWI began to use the measure in In 2008, out of a total of over 300,000 laboratory tests, we recorded 68 exceedances of regulatory standards, compared to a figure of 101 in Any exceedances are reported to the DWI and are thoroughly investigated by our team of scientists. If there is any potential risk to public health, we work closely with local health protection teams and local authorities to provide timely, appropriate advice to customers. Drinking water compliance at water treatment works Drinking water compliance in our distribution system We monitor drinking water quality in our distribution systems by sampling both at supply points and at randomly selected customer taps. Supply points are typically water treatment works or some of our larger service reservoirs. At supply points we monitor for parameters which do not change in concentration as they pass through our network of pipes, for example pesticides, sulphate and nitrate. Compliance at supply points was excellent in The low number of exceedances we did record were due to either the presence of single spores of the bacterium Clostridium perfringens, or naturally occurring sulphate from a groundwater source. What do we mean? Parameters chemical substances or microbiological organisms which are monitored in drinking water. Exceedance when we detect a particular parameter outside regulatory specifications or limits. The quality of water leaving our water treatment works was excellent in 2008, and coliforms were absent in per cent of the 16,438 microbiological samples taken at our works [2007: 99.96]. Drinking water compliance at storage points Treated water is often stored in service reservoirs or water towers before it is distributed to our customers. Compliance at our storage points was also excellent, with coliforms absent from per cent of the 20,743 microbiological samples taken in 2008 [2007: 99.94]. We had a single E.coli exceedance at one service reservoir. This was thoroughly investigated, while the service reservoir was taken out of supply for a brief period for inspection and cleaning. In 2008 we recorded a significant reduction in the number of exceedances at customer taps. This included a 50 per cent reduction in the number of microbiological exceedances. As in previous years, many of the microbiological exceedances that occurred were found, following investigation, to be due to the condition of customers tap fittings. This highlights the continued need for customers to ensure that taps used for drinking and cooking purposes are properly maintained and regularly cleaned. More information on keeping water healthy in your home can be found on our website at 3 Anglian Water Services Limited Drinking Water Quality Report 2008

5 Working with our customers The number of customers contacting us with concerns about the quality of their drinking water continued its downward trend in We are continuing to improve the information on drinking water quality available to customers on our website. 68% Customer complaints are down by 68 per cent since Over the last 10 years, numbers of complaints have reduced from almost 21,000 to fewer than 8,000 a year. This reflects the continued investment we have made in our distribution system. As a result of improvements we have made to our operational practices, the number of customers reporting that their water supply is white or cloudy due to the presence of air bubbles has gone down considerably. Water can appear cloudy following work on our system, such as the repair of burst mains, but this can also be caused by the condition of domestic plumbing systems. We encourage our customers to lag their hot water pipes and to check that their stop taps are fully opened. These are simple ways to minimise the likelihood of cloudy, aerated water. A significant number of complaints we receive from customers report TCP -like tastes and smells. These tastes and smells can arise when the very low amounts of chlorine present in drinking water react with materials in domestic appliances in customers homes. The most common sources of the problem are some plastic and rubber parts in kettles and the hoses connected to dishwashers and washing machines. These tastes and smells are extremely simple to eliminate for example, by ensuring that there is always a non-return valve between any hoses and the appliance. We are working to reduce the number of customers with concerns about their drinking water quality. We encourage customers experiencing a TCP -like, medicinal, metallic or bitter taste or smell, or who notice their water is cloudy, to visit our website at for advice and information. Number of customer complaints about drinking water quality Number of customer complaints 25,000 20,000 15,000 10,000 5, Anglian Water Services Limited Drinking Water Quality Report 2008

6 Safeguarding our customers drinking water We investigate all concerns about drinking water quality immediately, and work with local health protection and environmental health teams to safeguard our customers drinking water. For more information see our website at Caption Keeping here customers informed Any actual or potential deterioration in the quality of drinking water, whether identified by our own monitoring or by our customers, is investigated immediately. We liaise with local health protection and environmental health teams during any significant drinking water quality incidents, and report these to the DWI, which independently investigates them. Pitsford water treatment works In June 2008 we faced a challenge with a significant water quality incident when we detected Cryptosporidia in routine water quality samples taken from the Pitsford water treatment works in Northamptonshire. We took the precautionary approach of advising customers in around 108,000 homes to boil their tap water. More than 300 Anglian Water staff and contractors worked around the clock during this period to restore drinking water supplies to their usual extremely high standard and to keep customers fully informed both directly and through the local media in a high-profile communications campaign. We also worked very closely with the DWI, health protection agencies and community organisations. The incident was independently investigated and the DWI made a number of recommendations, all of which we have acted upon. The DWI commended us for our prompt response to the problem and for our actions to protect public health as part of a multi-agency team. We apologised unreservedly to our customers for the inconvenience caused and made goodwill payments to customers in affected areas. We have undertaken a comprehensive review across all Anglian Water sites to help prevent a similar incident from occurring again. In addition, we have shared the lessons we have learnt in detecting and rectifying the problem with external agencies, including health protection and environmental health teams, and with other water companies. Hydrocarbon contamination of customer pipework We continue to encourage commercial and domestic customers to manage disposal of petrol, oil and other fuels carefully and responsibly, particularly keeping them away from water pipes and drains. In 2008, we recorded 22 incidents of contamination at customers taps by hydrocarbons, such as petrol or fuel oil. In the last five years, almost 100 domestic and commercial properties across our region have been affected by hydrocarbon contamination, caused predominantly by the accidental spillage of fuel near to plastic water pipes on customers properties. Fuels can permeate plastic pipes, giving an unpleasant taste or smell and leading to elevated levels of hydrocarbons in drinking water. In the majority of cases, the only solution is costly replacement of the pipework. For more information on the safe management and disposal of fuels, please contact your local Environmental Health Officer. 5 Anglian Water Services Limited Drinking Water Quality Report 2008

7 Drinking water quality improvement programmes Nitrate removal plant Norfolk, completed in 2008 We are investing approximately 100 million in the period on schemes to manage the quality of water we take from the environment. This investment is mainly focused on the installation of new nitrate reduction treatment at sites where the groundwater nitrate concentrations are rising due to the use of fertilisers. The DWI closely monitors delivery of our programme and we are on track to complete all the new water treatment schemes by the end of March Eighty per cent of the programme was completed by the end of 2008, following the installation of a further eight nitrate reduction schemes across the region ahead of their target date. Drinking Water Safety Planning and our Final Business Plan for Risk management and risk assessment are essential to ensuring reliable supplies of high-quality drinking water, and we follow the principles of Drinking Water Safety Planning (DWSP) as we abstract water from our sources, treat this water at our treatment works and distribute drinking water to our customers. DWSP involves assessing potential hazards and identifying control measures at each stage in the water supply system, from source to tap, and then undertaking a risk assessment of the impact on drinking water supplies. DWSP is now a regulatory requirement, and in September 2008 we submitted risk assessments for all our supply systems to the DWI. We identified a small number of risks as part of this process. The quality of some of the groundwater we use is on a deteriorating trend. We also need to ensure water at customers taps meets the new tougher standards for lead of 10 microgrammes per litre (µg/l) which comes into force in The investment required to reduce risk from these issues is included in our Final Business Plan for the period 2010 to This Plan was submitted to the Water Services Regulation Authority (Ofwat) in April 2009, who will make their final determination later in We plan to develop our existing working relationships with a wide range of partners on projects including catchment management work with the Environment Agency, Natural England and the agricultural community, and joint lead pipework replacement schemes with local authorities and housing associations. We continue to develop our network of key stakeholders as we prepare for the investment period. An overview of our Final Business Plan and our Strategic Direction Statement are on our website at 6 Anglian Water Services Limited Drinking Water Quality Report 2008

8 Drinking water quality results 2008 Regulatory standards for drinking water in the UK are some of the toughest in the world. The following pages provide a full summary of all the regulatory monitoring of drinking water we carried out in For full details of the drinking water quality in your area, visit the drinking water quality page on our website at and simply type in your postcode. The UK Government s Water Supply (Water Quality) Regulations 2000, as amended in 2007, detail a series of numerical standards water supplies must comply with. These standards are based on the 1998 European Drinking Water Directive (Ref 98/83/EC), which in turn derives its standards from the World Health Organization (WHO). The WHO guideline values represent the concentration of a parameter that does not result in any significant risk to health for the consumer over a lifetime of consumption. The regulations for England and Wales go beyond the European Directive standards, and include a number of national standards and additional monitoring requirements. This combination of standards is among the toughest in the world, and is designed to protect drinking water quality and public health. Specific parameters are measured at treatment works, storage points and in our public water supply zones (PWSZs). PWSZs are groups of villages or towns who receive water from the same water treatment works. Monitoring of parameters in supply zones is either carried out at the supply point for the zone, typically the water treatment works, or a service reservoir or water tower, or directly from randomly selected customer taps. Water samples are analysed at our fully accredited laboratories in Lincoln and Huntingdon. Our laboratories also provide a first-class analytical service to a wide range of external customers, including other water companies and local authorities. The tables on the following pages provide details of our entire 2008 regulatory monitoring programme. The regulations specify the numbers of samples required from each stage in the supply system, and detail the parameters to be measured. The supply of high-quality drinking water, in a region where high population growth and climate change are occurring, is a key priority for Drinking Water Quality Report For more detail on how we ensure water is supplied to our customers at the highest possible standards go to 7 Anglian Water Services Limited Drinking Water Quality Report 2008

9 Water treatment works 2008 Excellent compliance with standards. Coliforms were detected at four water treatment works, and turbidity exceedances were recorded at five water treatment works. European standards We thoroughly investigated all exceedances, and took appropriate remedial action. Parameter Total number of tests Number of tests greater than PCV 1 Number of works with failures Nitrite 2, TOTAL 2, National standards Parameter Total number of tests Number of tests greater than PCV 1 Number of works with failures Coliform bacteria 16, Cryptosporidium 1,554 not applicable not applicable E. coli 16, TOTAL 34, Additional monitoring requirements Indicator parameter Total number of tests Tests exceeding specifications Colony counts after 3 days at 22 C 16, Colony counts after 48 hours at 37 C 16, Residual disinfectant total 16, Turbidity 9, TOTAL 59, Prescribed concentration or value Number of works with failures 8 Anglian Water Services Limited Drinking Water Quality Report 2008

10 Storage points 2008 Excellent compliance with standards. All storage points were compliant with the standard for coliforms. A single E.coli exceedance was recorded at one storage point. We thoroughly investigated this, and took appropriate remedial action. National standards Parameter Total number of tests Number of tests greater than PCV 1 Number of storage points failing standard Coliform bacteria 2 20, E. coli 20, TOTAL 41, Additional monitoring requirements Indicator parameter Total number of tests Number of tests exceeding specifications Colony counts after 3 days at 22 C 20, Colony counts after 48 hours at 37 C 20, Residual disinfectant total 20, TOTAL 62, Prescribed concentration or value 2 A storage point is considered to be compliant if 95 per cent of samples are free from coliform bacteria. Number of storage points failing specifications 9 Anglian Water Services Limited Drinking Water Quality Report 2008

11 Supply points 2008 There were no exceedances of European or national standards at supply points in European standards Parameter Total number of tests Number of tests greater than PCV 1 1,2 Dichloroethane 1,194 0 Antimony 1,157 0 Arsenic 1,145 0 Benzene 1,194 0 Boron 1,193 0 Bromate 1,178 0 Cadmium 1,148 0 Cyanide 1,188 0 Fluoride 1,194 0 Mercury 1,189 0 Selenium 1,157 0 Tetrachloroethene/Trichloroethene 1,194 0 Trihalomethanes (THMs) Pesticides total substances 1,210 0 Acidic herbicides (5) 3,115 0 Organochlorine insecticides (4) Substituted phenyl urea herbicides (5) 6,000 0 Triazine herbicides (6) 7,128 0 Other pesticides (9) 1,809 0 TOTAL 34,240 0 National standards Parameter Total number of tests Number of tests greater than PCV 1 Tetrachloromethane 1,194 0 TOTAL 1, Prescribed concentration or value 10 Anglian Water Services Limited Drinking Water Quality Report 2008

12 Additional monitoring requirements Supply points 2008 Excellent compliance with additional monitoring requirements. We detected Clostridium perfringens spores at two supply points in Both results were immediately investigated. Four samples from a single supply point exceeded the specification for sulphate due to naturally occurring sulphate in the groundwater supplying the area. Six tests exceeded the specification for gross alpha activity. Each of these triggered a test for the total indicative dose of the water supply, and all were compliant with the specified value. Indicator parameter Total number of tests Number of tests exceeding specifications Chloride 1,194 0 Clostridium perfringens 2,877 2 Conductivity 3,484 0 Radioactivity gross alpha Radioactivity gross beta Radioactivity total indicative dose Sulphate 1,193 4 Total Organic Carbon (TOC) 1,191 0 TOTAL 10, Both of these are measured as part of the calculation of total indicative dose. 2 Total indicative dose is only measured if the screening values for gross alpha or gross beta activity are exceeded. 11 Anglian Water Services Limited Drinking Water Quality Report 2008

13 Public water supply zones 2008 Excellent compliance with European and national standards. A low number of exceedances of the standards for benzo (a) pyrene, iron, manganese, aluminium, nitrite and turbidity occurred due to localised issues in our network of pipes. Exceedances of the standards for nickel and taste and smell were investigated and found to be due to issues with plumbing in customers homes or premises. European standards Parameter Total number of tests Number of tests greater than PCV 1 Antimony 76 0 Benzo (a) pyrene 1,457 1 Copper 1,630 0 E. coli 11,691 0 Enterococci 1,465 0 Fluoride 40 0 Lead 1,631 0 Nickel 1,636 4 Nitrate 2,894 0 Nitrite 2,896 1 Nitrate/Nitrite formula 2,894 0 PAH sum of 4 substances 1,457 0 Pesticides total substances 33 0 Other determinands 3,483 0 TOTAL 33,283 6 National standards Parameter Total number of tests Number of tests greater than PCV 1 Aluminium 2,377 2 Colour 2,643 0 Iron 3, Manganese 2,658 2 Organoleptic odour 2,569 5 Organoleptic taste 2,505 1 Sodium 1,455 0 Tetrachloromethane 28 0 Turbidity 3,036 1 TOTAL 20, Prescribed concentration or value 12 Anglian Water Services Limited Drinking Water Quality Report 2008

14 Public water supply zones 2008 Excellent compliance with additional monitoring requirements. 16 samples from customer taps contained coliform bacteria, and a number of these were found to be caused by issues with customers plumbing. One test exceeded the specification for gross alpha activity. This triggered a test for the total indicative dose of the water supply, which was compliant with the specified value. Additional monitoring requirements Indicator parameter Total number of tests Number of tests exceeding specifications Ammonium 3,397 0 Chloride 26 0 Clostridium perfringens 33 0 Coliform bacteria 11, Colony counts after 3 days at 22 C 11,695 0 Colony counts after 48 hours at 37 C 11,696 0 Conductivity 30 0 Hydrogen ion (ph) 2,528 0 Radioactivity gross alpha Radioactivity gross beta Radioactivity total indicative dose Residual disinfectant total 11,705 0 Sulphate 26 0 Total Organic Carbon (TOC) 26 0 TOTAL 52, Both of these are measured as part of the calculation of total indicative dose. 2 Total indicative dose is only measured if the screening values for gross alpha or gross beta activity are exceeded. 13 Anglian Water Services Limited Drinking Water Quality Report 2008

15 For more information on drinking water quality, contact us: Online Our website has a wealth of information on drinking water quality and you can find results for every supply zone via our postcode search. Visit Write to Drinking Water Standards Manager Anglian Water Services Henderson House Lancaster Way Ermine Business Park Huntingdon Cambridgeshire PE29 6XQ Telephone our customer helpline us custservice@anglianwater.co.uk Our Strategic Direction Statement We published our Strategic Direction Statement in December It details our strategy to deliver outstanding service, reliability and value for money for our customers in the period 2010 to Read or download our Strategic Direction Statement at Visit our website for our full range of customer, business and recreation publications Doc. Ref. No. AW160/07/09 14 Anglian Water Services Limited Drinking Water Quality Report 2008